1. Field of Invention
The invention relates to a method and apparatus for quickly cooling fluids and maintaining fluids at a low temperature. The apparatus is particularly useful for rapid cooling of medical fluids.
2. Description of Related Art
In the past, there have been various refrigeration devices for cooling and/or storing fluids at a low temperature. Such devices include conventional refrigeration devices and thermoelectric cooling devices.
Conventional refrigeration devices cool utilizing a refrigeration box, expansion valve, compressor and condenser. The expansion valve is where liquid refrigerant expands and changes to cold vapor. The cold vapor absorbs heat and travels to the compressor. The compressor compresses the refrigerant vapor. The condenser discharges absorbed heat into the surrounding ambient, converting the compressed vapor into high pressure liquid refrigerant. Another expansion valve reduces the liquid pressure cooling the liquid refrigerant. The cooled liquid refrigerant is then returned to the first expansion valve and the cycle repeats.
Conventional thermoelectric cooling devices are similar in principle to the conventional refrigeration devices. However, the refrigerant in both liquid and vapor form is replaced by two dissimilar conductors. The surface of the refrigeration box is cooled through adsorption of energy by electrons as they pass from one semiconductor to another. The compressor is replaced by a direct current power source which pumps the electrons from one semiconductor to another. A heat sink replaces the condenser, discharging accumulated heat energy from the system.
However, none of these devices are capable of quickly cooling fluids to a very low temperature and maintaining the fluids at a very low temperature. Such devices are inefficient as they consume large amounts of power to provide cooling and to maintain fluids at a desired temperature ready when needed. Additionally, such devices have complex moving parts, which increase the cost of manufacture and require frequent maintenance.